The present invention relates to testing electronic devices, and more particularly to separating the devices according to their test results.
Many different characteristics of electronic devices are tested during and after their manufacturing process. Some of the tests are simple pass/fail tests, such as power-up tests, while other tests are more complex, such as system level tests. One, relatively complex test is a speed rating test to determine the highest operating speed at which a device can performed. In such a test, a device, or plurality of devices, are placed in a test station for testing, and depending upon the test results, each device is then removed from the test station and sorted, or binned, according to its operating speed.
Because of the vast volume of electronic devices often being tested, efforts to automate the testing process are common in the industry. One typical automated improvement to the testing process is a robotic picker/placer arm which positions devices under test in a test station as well as positions them in output containers after testing. When utilizing automated robotic arms, some predetermined positioning and arrangements of the output containers are necessary so that the picker/placer arm""s different movements can be programmed into it.
Each particular test-result category is associated with a xe2x80x9cbin,xe2x80x9d thereby ensuring that devices with similar test results are identically binned. There is a distinct bin path on the output of the tester for each test-result category which accomplishes physical segregation of the devices under test. In other words, after testing, the test output handler forwards a device along an appropriate bin path such that similar devices are aggregated at a bin, which represents an aggregation of similarly categorized devices. The bin may be manifested by a tray or other container that will hold the categorized devices.
A test station, therefore, typically has multiple locations, or bins, where devices, after testing, are placed depending on their test performance. At each bin, a tray or other container is used to collect all the devices that are output to that particular bin. Usually, bins are organized in a predetermined arrangement scheme on some type of platform near the output of the test station. Upon test completion, the picker/placer arm extracts from the test station an electronic device and places it, depending on the bin identified by the test result, in an appropriate tray. The end result is that electronic devices having similar characteristics or performance constraints are segregated accordingly. Once a tray is filled, an operator removes the tray to a holding area and places an empty tray in its place.
The placement of the correct tray at the correct location, initially and during testing, is one step of the testing process that introduces errors. Placing a tray at an incorrect location, known as xe2x80x9cbin mixingxe2x80x9d, is costly and time consuming because it requires the resulting misplaced electronic devices to be retested.
The prior art fails to provide an error-free and efficient method for ensuring the output trays of a test station are always properly positioned. Bin mixing, due to the current methods of testing of electronic devices, adversely affects both manufacturing quality assurance and cycle time and increases manufacturing costs.
There is a need for an error-free method of positioning output trays at a test station. These and other needs are met by embodiments of the present invention which provide a test station with multiple output bins on an output platform that receives an electronic device under test. At each of the different output bins on the output platform, replaceable trays which accept the electronic devices are positioned. After testing of the device is completed, an automatic device handler removes a device from the test station and places it at an appropriate bin based on the test results. As the trays at each bin become full, the trays are removed and empty trays are placed at the bin. A unique guide is located near each bin position on the output platform and each tray is shaped to match one of the guides. Thus, when a tray is placed at a bin location, it will properly fit at only one bin. In certain embodiments, all of the trays are similar and a clip which attaches to a side of a tray is used to provide the matching shape to one of the bin guides.
The needs are also met by embodiments of the present invention which provide for a platform surface, for supporting a plurality of trays, on which a plurality of guides are arranged; each tray being configured such that it only aligns with one of the guides. When the trays are positioned on the platform so that each is aligned with its corresponding guide, then each tray can occupy only a single location on the platform.
The needs are also met by embodiments of the present invention which provide for a platform which can receive articles only at discrete locations, each of these locations having an associated guide, and a plurality of trays, each of which is configured to match only one of the guides. When the trays are supported on the platform, each tray is positioned at the discrete location that is associated with the guide that matches that particular tray.
The foregoing features, as well as other aspects and advantages, of the present invention, will become more apparent from the following detailed description, claims and drawings.